Gradient Genogeographic Analysis of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L. Populations in Europe

Gradients of Nei's genetic distances between 15 samples of Pinus sylvestris L. trees were analyzed along three submeridional transects, from Scandinavia to the Mediterranean and Transcaucasia. As a result, distinct chorogenetic differentiation was revealed between the populations of this species growing in climatically specific regions of northern and southern Europe. Considerable Nei's distances (DN = 0.045–0.056) and their gradients, combined with differences in stable phenotypic characters (the composition of monoterpenes and morphological parameters of cones) determined at the Pyrenean and Caucasian mountain borders, suggest that the P. sylvestris species structure includes two South Eurasian subspecies, the Pyrenean P. sylvestris L., ssp. iberica Svoboda and the Transcaucasian P. sylvestris L., ssp. hamata (Stev.) Fomin.     

A system of Pleistocene refugia for Pinus sylvestris L. in the southern marginal part of the species range

An allozyme analysis of 67 Pinus sylvestris L. populations distributed over the entire species range has provided a basis for determining locations of 12 hypothetical Pleistocene refugia (HPRs) in its southern marginal part and estimating their relative contributions to the gene pools of seven phylogeographic population groups (PPGs) in the glaciated zone of the range. Using Nei’s (1978) minimum genetic distances (DN78 < 0.015) reflecting similarities and differences in allele frequencies between PPGs and the refugia, it has been shown that the main contributions to the P. sylvestris gene pool in Central Europe, Scandinavia, and the Russian Plain were probably made by the Balkan and Southern Ural refugia, and in Western and Central Siberia, by the Southern Ural, Turgai, and Southern Siberian mountain refugia.     

An outline of the theory of the genetic divergence of dry-land and bog populations of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.

The thesis of the genetic divergence of Pinus sylvestris L. populations that have spread to bogs from the original dry-land populations has been deduced from the concept of the cyclicity of helio- and geophysical processes, derivative postulates on climatic cycles, formation of Holocene high bogs, contrasting differentiation between their environment and that of dry meadows, and the resultant changes in the vectors of microevolutionary factors and strong reproductive isolation between these populations. Logical genetic, ecological-phenotypical, and geographic consequences of this theory have been verified by factual data and general laws known to date. The interpolational and predictive roles of the new theory are demonstrated.     

Genetic differentiation of <Emphasis Type="Italic">Pinus mugo</Emphasis> Turra and <Emphasis Type="Italic">P. sylvestris</Emphasis> L. populations in the Ukrainian Carpathians and the Swiss Alps

The allozyme analysis of six local populations of Pinus mugo Turra and six populations of P. sylvestris L. in the Ukrainian Carpathians, Swiss Alps, and Schwarzwald has shown a higher polymorphism and greater interpopulation differentiation of the Carpathian group of P. mugo populations compared to the Alpine group (Nei’s genetic distance DN ₇₈ at the level of geographic population group is −0.023). A genetic differentiation of DN ₇₈ = 0.049 between these populations, which are isolated by a distance of more than 1000 km, has been found. This confirms the existence of the subspecies P. mugo ssp. mugo and P. mugo ssp. uncinata in the Carpathians and Alps, respectively. The hypothesis is put forward that the former subspecies has been formed in the Balkans and the latter, in the Pyreneans. It has been demonstrated that regional populations and geographic groups of P. sylvestris are less differentiated than those of P. mugo.     

Geno- and Phenogeographic Analysis of Pinus sylvestris L. Populations along the Transect Extending from the Northern to Southern Boundary of the Species Range

Nei's genetic distances (Nei, 1972, 1978) between 12 Scotch pine (Pinus sylvestris L.) populations were determined using isozyme analysis. The gradients of these distances along the 1500-km meridional transect in the Transural Region and Northern Turgai from the pre-forest-tundra subzone (the Synya River basin) to the southern steppe (the Naurzumskii forest) were calculated. We discovered that the genetic distance gradients (GDGs) progressively increase in the direction from the northern boundary of the range to the southern boundary of the forest-steppe zone and sharply increase in the insular forests growing in the steppe zone. The results of cluster analysis and Mahalanobis distance gradients with respect to a set of morphological characters of the cones provide evidence that Scotch pine populations of the forest zone share somewhat the same gene pool, whereas the group of Scotch pine populations in the insular forests of Northern Turgai is obviously differentiated phenogenetically from the insular forests of the Tobol region, which grow farther to the north.     

Insularization and polymorphism in marginal island populations of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.

Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km² and increases to the level observed in the center of the range when the population area exceeds 50–100 km². A chorogenetic classification of marginal P. sylvestris populations is proposed.     

Genetic Differentiation of the Ural Endemic <Emphasis Type="Italic">Gypsophila uralensis</Emphasis> (Caryophyllaceae) in Relict Fragments of Its Range in Northwestern European Russia

Molecular genetic methods (AFLP and ITS1–5.8S–ITS2 rDNA analysis) have been used to study the level and structure of genetic diversity in relict populations of the Ural endemic Gypsophila uralensis Less. in the northeast of European Russia. Intraspecific genetic differentiation is most clearly manifested between G. uralensis Less. subsp. pinegensis (Perf.) Kamelin locally endemic to the north of Europe (Arkhangelsk oblast, locus classicus) the population of G. uralensis Less. subsp. uralensis on limestone outcrops along the Shchugor River, the Subpolar Urals. The cluster of Timan populations (on limestone outcrops along the Svetlaya, Pizhma, and Myla rivers) is autonomous and genetically heterogeneous. Genetic distances between model G. uralensis s.l. populations are correlated with geographic distances. The size and abundance of relict populations show a descending gradient in the forest zone, and parameters of their genetic diversity [1] and unbiased expected heterozygosity have been found to decrease along this gradient.     

Genogeography of <Emphasis Type="Italic">Pinus sylvestris</Emphasis> L. populations in the Greater Caucasus and Crimea

Allozyme analysis of 18 Pinus sylvestris L. populations from seven landscape-geographic groups has been performed in the Greater Caucasus, Crimea, and Russian Plain. The results show that populations of the Mt. Elbrus region (isolated by high mountain ridges) are characterized by lower polymorphism and most distinct differentiation (at the level of geographic race) from other populations, which are differentiated from each other at the level of geographic groups. Genetic gradients (boundaries) between populations reach a maximum on transects across the Greater Caucasus Range, and Transcaucasian populations are more similar to populations of the Russian Plain, compared to North Caucasian populations, which confirms the hypothesis of ancestral connections between their gene pools.     

Role of genetic factors in landscape-geographic variation of the water vole (Arvicola terrestris L.)

The geographic variation of the water vole Arvicola terrestris L. has been analyzed with respect to two linear combinations of craniometric characters with the highest additive heritability (h ² = 0.59 and h ² = 0.52). The greatest differences have been revealed between the territorially close montane and piedmont populations. The lowland and montane populations have proved to differ to the smallest extent, despite their spatial and altitudinal separation. Selection under extreme conditions that leads to similar phenotypic results may be based on the common genetic background of these populations, irrespective of considerable distances between them and different environmental conditions in their habitats.     

Spatial distribution and karyotypic composition of Anopheles mosquitoes (Diptera, Culicidae) in the environs of Teletskoye Lake

The species composition and inversion structure of Anopheles micropopulations have been studied in the environs of Teletskoye Lake, the Altai Republic. Two Anopheles species, A. messeae and A. beklemishevi, have been identified cytogenetically: Their zonal distribution has been determined, reflecting specific climatic features in the southern and northern parts of the lake. Intraspecific chromosomal polymorphism has been revealed in both mosquito species, with the inversion and karyotypic diversity being higher in the southern larval populations of A. messeae.     

Gradient analysis of the chrogenetic structure of lowland and highland scotch pine populations

Gradients of genetic distances (GGDs) between 26 adjacent cenopopulations of Scotch pine (Pinus sylvestris L.) along the transects through the distinct landscape-ecotopic isolation borders were analyzed graphically. The results made it possible to reveal and quantitatively estimate gradients and borders of gene-pool structural patterns in populations of this species in the central part of Northern Eurasia. In lowland areas, the most distinct borders were found between pine populations growing on dry lands and bogs (Pineta sphagnosa) in the forest zone of the Transural region, as well as between the Arakaragaiskii and Amankaragaiskii island pine forests in the steppe zone (Northern Turgai). In highland areas (the Urals and the Carpathians), the greatest GGDs were observed between low-mountain (about 600 m above sea level) and middle-mountain (850–900 m) populations. Analysis of GGDs is a promising gene-geographic method for determining population borders and studying the chorogenetic structure of species.     

Specific Cytogenetic Characteristics of Pinus cretaceae and Pinus sylvestris

A comparative cytogenetic study has been performed in four populations of two pine species, Pinus cretaceae Kalen. and P. sylvestris L., growing on sandy and chalky substrates in Voronezh and Belgorod oblasts. Significant differences in the parameters of mitotic and nucleolar activities, as well as the rate and spectrum of mitotic pathology, between populations of P. cretaceae and P. sylvestris and between populations of P. cretaceae growing under different conditions have been found. Populations of P. sylvestris growing on sandy and chalky substrates differ from each other in nucleolar activity. These differences may be adaptive and reflect the characteristic metabolic patterns and biological plasticity of pines growing under specific conditions.     

Reproductive isolation and disruptive selection as factors of genetic divergence between Pinus sylvestris L. populations

Generalizations are made on the basis of results obtained in the course of long-term, stationary quantitative studies on phenogenetic divergence of P. sylvestris populations growing in an upland bog and the adjacent dry land area in the pre-forest-steppe zone of Western Siberia. Contrasting differences between the two edaphoecotopes and almost complete phenological reproductive isolation of populations from year to year are demonstrated. It has been found that root morphogenesis in the F ₁ progeny of pine from the bog population grown under uniform ecological conditions in the dry land area is characterized by elimination of the vertical phenotype, with the alternative lateral phenotype type being dominant in 7- to 22-year seedlings. Significant allozyme differentiation and distinct chorological boundary between the dry-land and bog populations have been revealed. The hypothesis of their genetic divergence in the Holocene is proposed, with this phenomenon being explained by the cumulative effect of disruptive selection and strict reproductive isolation in two contrasting environments.     

Morphophysiological responses of Pinus sylvestris L. and Picea obovata Ledeb. to industrial pollution under conditions of Northwestern Russia

Morphophysiological parameters of needles have been studied in Scots pine (Pinus sylvestris L.) and Siberian spruce (Picea obovata Ledeb.) trees of different life states growing under conditions of industrial air pollution with sulfur and heavy metals. Three functional clusters (tentatively named the initial, transitional, and disastrous clusters), each characterized by a certain metabolic status, have been revealed, and their quantitative and qualitative structure has been evaluated. The morphophysiological responses of pine and spruce are shown to be qualitatively different, depending on differentiation of trees with respect to vitality under conditions of industrial pollution. Probable factors accounting for these differences are discussed.     

Genetic divergence of eastern European and Tobol populations of Calluna vulgaris (L.) Hull.

Analysis of geographic variation of chloroplast DNA in the eastern European and western Siberian (Tobol) groups of Calluna vulgaris populations isolated from each other for a long period of time has revealed distinct differentiation between them. It has been shown that three populations growing in the Russian Plain and Karelia share two haplotypes characteristic of central Europe, while three Tobol populations contain one haplotype F occurring in Sweden. These results confirm the hypothesis of genetic divergence between the Tobol and eastern European groups of C. vulgaris populations.     

Intra- and interspecific morphological variation of some European terrestrial orchids along a latitudinal gradient

Morphological trait variation in populations of rhizomatous (Cypripedium calceolus, Listera ovata) and root-tuber orchid species (Platanthera bifolia, Gymnadenia conopsea) has been studied along a latitudinal gradient in Europe. It has been shown that the structure of shoots changes with transition from the center to the northern or southern periphery of the species range. The reduction in the number of metameres at the range periphery is more distinct in orchids with multimetameric shoots, compared to those with oligometameric shoots. The plasticity of shoot structure observed along the geographic gradient is contingent on climatic factors and can be manifested regionally in cases of long-term temperature deviations. Other morphological parameters, such as shoot height and the sizes of leaves and flowers, can serve as indicators of ecological conditions in habitats.     

Population structure and dynamics of Monotarsobius curtipes (Myriapoda, Chilopoda) at the northern periphery of the species range

Studies on the population structure and dynamics of the stone centipede Monotarsobius curtipes C. Koch in soils of the northern Kola Peninsula have shown that, with respect to abundance and biomass, this species is a dominant of the soil macrofauna and, in particular, of the trophic group of zoophages. Life in high northern latitudes does not disturb the sex and age structure of populations but limits the reproductive activity of these centipedes. Specific biological features of M. curtipes at the northern periphery of its range include the absence of repeated breeding, completion of several developmental (age) stages within a short growing season, and long ontogeny involving several winterings.     

Technogenic morphological variation of the pygmy wood mouse (Sylvaemus uralensis pall.) in the Urals

Methods of geometric morphometrics have been used to compare the ranges and directions of geographic and technogenic forms of variation in the morphology of the mandible in Ural populations of pygmy wood mice (Sylvaemus uralensis Pall.) exposed to different types of pollutants (radionuclides, fluorides, and toxic petrochemical products). The range of variation in the mandible morphology consequent to chronic radiation exposure in the zone of the Eastern Ural Radioactive Trace is commensurate to the range of geographic variation of the species observed in the Middle and Southern Urals. Unspecific manifestations of variation have been revealed, which apparently result from exposure to technogenic pollutants of different origin. A probable contribution of technogenic variation to rapid morphogenetic rearrangements in populations is discussed.     

The hypothesis of hydrochorous dissemination of populations of conifers

A comparative analysis of field observations and experiments on the distance and rate of dispersal of self-sown Scotch pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) progeny has shown that the rate of their hydrochorous dissemination downstream is an order of magnitude higher than the rate of dispersal in upland areas. A hypothesis assigning priority to the role of hydrochory in the expansion of conifer populations to the tundra (periglacial) zone along with climate warming has been formulated and substantiated by comparative isozyme analysis of populations in transects lying along and across rivers.     

Differentiation of cryptic wood mice species of the subgenus <Emphasis Type="Italic">Sylvaemus</Emphasis> under different ecogeographic conditions in the Northern Caucasus

Based on analysis of the frequencies of nonmetric cranial characters, the ratio of interpopulation and interspecific differences has been studied in populations of two genetically identified cryptic species of wood mice, A. uralensis and A. ponticus, living under different ecological conditions in the Northern Caucasus. Hybridization between these species has not been reported previously, but interspecific phenetic distances indicate that differences between them do not exceed the level characteristic of subspecies, with morphological differentiation between A. uralensis populations of the Central and Western Caucasus being weakly expressed. It is hypothesized that the low level of intra- and interspecific differences is explained by the sympatric and symbiotopic origin of both species in the Western Caucasus. This may account for the retention of their similarity in ecological requirements for the environment and, consequently, only slight morphological disparity in similar biotopes.